New A's reliever Luke Gregerson might be the best setup man of all time, and he's something of a badass, too.

Just ask former A's closer Huston Street, Gregerson's teammate in San Diego and the beneficiary of all those leads that Gregerson handed to him.

"Luke is an absolute stud," Street said. "He's a tough guy, he takes the ball every day, and he's a leader, never selfish, always thinking about the team. He keeps people accountable, and I sincerely appreciated that. He is the guy who will say what needs to be said, and he made all of us better."

Gregerson, 29, holds the all-time single-season record for, well, holds. He had 40 in 2010, and though the hold might not be the most glamorous of statistics, that is a lot of leads maintained.

"I absolutely knew about it, even though it kind of goes under the radar," Gregerson said. "No one had any idea what was going on, but it's something I'm very proud of. It's like saves for a closer - that's what you get if you're a setup guy."

"It's a strange record to have, but baseball has been around a long time," Street said. "Any record is really, really hard to do. And it means I leaned heavily on Luke. I knew if there was a three-run lead going into the eighth, there was going to be a three-run lead going into the ninth."

In Sports Illustrated, former A's outfielder Jonny Gomes called Gregerson "El Filthy McNasty." That's a common sentiment among batters, because Gregerson has one of the best sliders in the game. That pitch, combined with high appearance totals every year, gives scouts pause, and there's speculation that the only reason San Diego would trade such a valuable pitcher (for outfielder Seth Smith) was concern over his health.

"I was hearing the exact same thing in 2009, then he made 80 appearances the next season," an AL scout said. "But that is a lot of sliders. Sooner or later, it catches up to you."

The A's are well aware of Gregerson's history - 363 appearances in five years - and assistant general manager David Forst said, "There is so much information in the medical file, any red flag, (trainer) Nick Paparesta is going to find it. There were none in Luke's."

Gregerson knows how to take care of himself. He is careful with his conditioning, he throws minimal warm-up pitches and he gets quick outs. In addition, he said, he doesn't throw his slider with the sort of torque many pitchers use. There's less "snap" involved because he throws it so loosely.

"A lot of pitchers put too much emphasis on turning it," he said, rotating his wrist. "I don't need to do that. ... My elbow has never bothered me."

Is the mileage taking a toll on the quality of his pitches, though? One scout called Gregerson "a warrior" but added, "I think the stuff might be diminishing." That made Street snort.

"I don't know how anyone could think that," he said. "You could see the situation, everyone in the building knows he's going to throw the slider, you, me, the fans, the umpires, and they'd still swing and miss."

An excellent sinker complements the slider so everything is moving either in or away, and also down. "You can't sit on one pitch or look for one location," pitching coach Curt Young said.

Because Gregerson works fast and has a quick delivery, hitters seldom get a chance to get comfortable. Then there is the deception, which includes sort of a funky leg kick.

"It has a lot to do with my arm slot," he said. "Hitters always say that the ball looks like it's behind my head and they don't see it until I release it, which is good, because I don't throw mid-90s."

Gregerson has landed in perhaps the best spot possible for a setup man who has had plenty of use. The A's have four potential setup men behind closer Jim Johnson: Gregerson, Sean Doolittle, Ryan Cook (when he returns from shoulder soreness) and Dan Otero. Gregerson will not have to work four or five nights in a row and should "stay fresher longer," he said.

And in the meantime, he'll be a positive clubhouse presence in the mold of the top-notch vocal leaders from whom he learned in San Diego, including former A's outfielders Mark Kotsay and Matt Stairs, plus Cliff Floyd and Brian Giles.

"You just want to get guys moving the right way," Gregerson said. "There is a time for fun, and a time to get down to business."

"He relishes and embraces that role," San Diego manager Bud Black said. "Luke is a true team guy with a lot of grit; he does not scare off.

"He's got a certain step to his walk that signifies his presence. And he's very talented."